Aromatic diamines containing ester groups and the production of polyurethane elastomers therefrom

ABSTRACT

NOVEL AROMATIC DIAMINES CONTAINING ESTER GROUPS WHEREIN THE AMINO GROUPS ARE IN THE M- AND/OR P-POSITION RELATIVE TO THE ESTER GROUP, AND WITH A SUBSTIUENT IN THE O-POSITION TO AT LEAST ONE AMINO GROUP ARE USEFUL TO PREPARE POLYURETHANE ELASTOMERS THEREFROM WITH AN ORGANIC DIISOCYANATE AND AN ORGANIC COMPOUND CONTAINING AT LEAST TWO HYDROXYL GROUPS AND HAVING A MOLECULAR WEIGHT OF FROM ABOUT 800 TO ABOUT 5000, AND IF DESIRED AN ORGANIC COMPOUND CONTAINING AT LEAST TWO HYDROXYL GROUPS AND HAVING A MOLECULAR WEIGHT OF FROM ABOUT 50 TO ABOUT 500.

United States Patent Office Patented Aug. 1, 1972 US. Cl. 260-775 AM 19Claims ABSTRACT OF THE DISCLOSURE Novel aromatic diamines containingester groups wherein the amino groups are in the mand/ or p-positionrelative to the ester group, and with a substituent in the o-position toat least one amino group are useful to prepare polyurethane elastomerstherefrom with an organic diisocyanate and an organic compoundcontaining at least two hydroxyl groups and having a molecular weight offrom about 800 to about 5000, and if desired an organic compoundcontaining at least two hydroxyl groups and having a molecular Weight offrom about 50 to about 500.

This is a continuation-in-part of copending application Ser. No.866,373, filed Oct. 14, 1969 and relates to novel aromatic diamines andto elastomeric polyurethanes prepared therefrom. More particularly, thisinvention relates to aromatic diamines containing ester groups and toelastorneric polyurethanes prepared therefrom and having good tensilestrength and elasticity.

This invention relates to aromatic diamines containing ester groups inwhich the amino groups are in the mand/ or p-position relative to theester group, and with a substituent in the o-position to at least oneamino group. Preferred substituents include halogen atoms, such as,fluorine, chlorine, bromine or iodine, among which chlorine isparticularly preferred, and alkoxy radicals containing from 1 to 4carbon atoms.

Diamines of this invention include those having the formula wherein Rrepresents an alkyl radical having from 1 to 20 carbon atoms whichoptionally can contain oxygen atoms, an aryl-, aralkylor cycloalkylradical and X represents an alkoxy radical having from 1 to 4 carbonatoms or a halogen atom; those having the formula H N NH! wherein Xrepresents a hydrogen or halogen atom and Y represents a halogen atom;those having the formula wherein A represents an alkylene radical havingfrom 2 to 6 carbon atoms which may be optionally branched and/or containoxygen, sulfur or atoms; those having the formula wherein each Xrepresents halogen and in which at least one substituent X is in theo-position to the amino group; and those having the formula wherein Rrepresents CH C H C H or iso-C H those having the formula i NH:

HaN

wherein R represents a, zH5, n-, 180-03117, n-, -0 11;

the compound having the formula the compound having the formula Hal 1the compounds having the formula HQN NH, 5

wherein n represents a number of from 2 to 6, the compound having theformula HzN-QO-E- OQ-NH;

and the compounds having the formula wherein n represents a number offrom 0 to 4.

The new aromatic diamines containing ester groups may be prepared bygenerally known processes. For example, diamines having the generalformula (ilO-O-R wherein X and R are as defined above, can be obtainedby reacting corresponding dinitrobenzoic acids of the formula (IJOOH ortheir acid halides with alcohols of the formula R--OH and subsequentlyhydrogenating the nitro groups by generally known methods, such as, forexample, by catalytic hydrogenation.

Compounds having the formula HzN NH:

wherein X and Y are as defined above, can be obtained, for example, byreacting nitrobenzoic acids of the formula or their acid halides withnitrophenols corresponding to the formula and subsequently hydrogenatingthe nitro groups into amino groups by generally known methods.

Diamines having the formula (ll-QC 0--0A--OC o-Q-or l HEN NH:

wherein X is as defined above, can be obtained, for example, by reactingphenols corresponding to formula for example, with diphenyl carbonate orphosgene, by generally known methods, and subsequently hydrogenating theresulting dinitrodiphenyl carbonates.

Compounds having the formula HEN (I? (1) NH:

wherein X and n are as defined above, may also be obtained in agenerally known manner by reacting nitrophenols corresponding to theformula -by the Schotten-Baumann method with dicarboxylic aciddihalides, such as, for example, with oxalyl chloride, succinic aciddichloride and glutaric acid dichloride, in the presence of aqueoussodium hydroxide, or by thermally esterifying the aforementioneddicarboxylic acids with the corresponding nitrophenols. The nitro groupsare subsequently hydrogenated into amino groups by generally knownmethods, such as, for example, in solvents such as methanol or dioxane,optionally in the presence ON of catalysts, such as, for example, Raneynickel or 2 platinum.

The following are examples of the novel compounds Y according to theinvention:

0 O-0CH= C 0-0-C,H, C 0O-CH C 00-C;H l

H7N NH: HzN N H2 HrN NH: HzN NE:

Generally, the novel diamine compounds may :be used, for example, asstarting materials in the production of dyes and plant protectionagents.

The compounds have proved to be particularly valuable as chain extendingagents in the production of plastics with elastomeric properties by theconventional isocyanate-polyaddition process.

Accordingly, this invention also relates to a process for the productionof polyurethane elastomers from an organic compound containing at leasttwo hydroxyl groups reactive with isocyanate groups and having amolecular weight of from about 800 to about 5,000, an organicdiisocyanate and an aromatic diamine as chainextender, wherein thearomatic diamine contains an ester group, the amino groups are in themand/or p-position to the ester group, and with a substituent in theo-position to at least one amino group.

If it is desirable to prepare hard polyurethane elastomers, i.e., thosehaving a Shore D hardness of from about 40 to about 90, it isparticularly advantageous to use in addition to the foregoing reactantsan organic compound containing at least two hydroxyl groups reactivewith isocyanates and having a molecular weight of from about 50 to about500.

Preferred chain-extending agents are diamines of the kind in which theamino groups are in the mor p-position to the ester group and having ahalogen substituent, preferably chlorine, or an alkoxy substituenthaving from '1 to 4 carbon atoms in the o-position to at least one aminogroup.

[Further preferred diamines to be used as chain extenders are thosederivated from 4-chloro 3,5 diamino benzoic acid by esterification withlinear or branched higher alcohols, which may contain hetero atoms, withphenols, araliphatic alcohols or cycloaliphatic alcohols. Considerableadvantage of the diamines according to the invention resides in the factthat, :by suitable choice of the alcohols, the melting point of thediamines can be modified so that liquid products result the handling ofwhich oifers advantages, since melting is not required. Diaminesrepresenting particularly preferred chain-extending agents for thepurpose of this invention include those having the formula wherin Rrepresents an alkyl radical having from 1 to carbon atoms whichoptionally can contain oxygen atoms, and aryl-, aralkylor cycloalkylradical and X represents an alkoxy radical having from 1 to 4 carbonatoms or halogen; those having the formula Hm NH:

wherein X represents a hydrogen or halogen atom and Y represents ahalogen atonuthose having the formula wherein A represents an alkyleneradical having from 2 to 6 carbon atoms which may be optionally branchedand/or contain oxygen, sulfur or N(R) (R=C -C alkyl) atoms; those havingthe formula HaN 0 NH Q X X wherein each X represents halogen and inwhich at least one substituent X is in the o-position to the aminogroup;

wherein n represents a number of from 0 to 4 and each X representshalogen and in which at least one substituent X is in the o-position tothe amino group; those having the formula wherein R represents CH C H -CH-, or iso- C H those having the formula those having the formulaewherein n represents a number of from 2 to 6; and those having theformulae wherein n represents a number of from to 4.

Suitable starting materials for the production of elastomericpolyurethanes according to this invention include those organiccompounds with at least two hydroxyl groups reactive with isocyanategroups and having molecular weights of from about 800 to about 5,000,preferably with molecular weights of from about 1,000 to about 3,000.

Any suitable hydroxyl polyester may be used such as linear or slightlybranched polyesters obtained, for example, from polycarboxylic acids andpolyhydric alcohols. Any suitable polycarboxylic acid may be used suchas, for example, oxalic acid, malonic acid, succinic acid, glutaricacid, adipic acid, pimelic acid, suberic acid, azelaic acid, brassylicacid, sebacic acid, thapsic acid, maleic acid, fumaric acid, glutaconicacid, diethylsuccinic acid, isophthalic acid, terephthalic acid,1,4-cyclohexanedicarboxylic acid, and the like as well as hydroxycarboxylic acids. Any suitable polyhydric alcohol may be used such as,for example, ethylene glycol, 1,3-propylene glycol, 1,2-butylene glycol,1,2-propylene glycol, 1,4-butylene glycol, 1,3-butylene glycol,1,5-pentane diol, 1,4-pentane diol, 1,3-pentane diol, 1,6-hexane diol,1,7-heptane diol and the like. The polyesters may contain double ortriple bonds in unsaturated fatty acid moieties.

Any suitable linear or slightly branched polyhydric polyalkylene ethermay be used such as, for example, the condensation product of analkylene oxide beginning with any suitable initiator. The initiator maybe difunctional compounds including water so that the resultingpolyether is essentially a chain of repeating alkylene oxy groups as inpolyethylene ether glycol, polypropylene polybutylene ether glycol andthe like; or the initiator may be any suitable active hydrogencontaining compound which may be a monomer or even a compound having arelatively high molecular weight including other active hydrogencontaining compounds as disclosed above. It is preferred that theinitiator have from 2 to 8 active sites to which the alkylene oxides mayadd including, for example, amines, alcohols and the like. Any suitablealkylene oxide may be used such as, for example, ethylene oxide,propylene oxide, butylene oxide, amylene oxide, tetrahydrofuran,epihalohydrins such as epichlorohydrin, styrene oxide and the like.Copolymers of this type may also be used. Any suitable initiator may beused including, for example, water, polyhydric alcohols, preferablyhaving 2 to 8 hydroxyl groups, aminoalcohols, amines preferably having 2to 8 replaceable hydrogen atoms bonded to nitrogen atoms. Phosphorousacids may also be used, but the phosphorus compounds are somewhatpeculiar in that a different mode of preparation may be required, asmore particularly set forth below. The resulting polyhydric polyalkyleneethers with the various bases of nitrogen, phosphorous and the like mayhave either primary or secondary hydroxyl groups or mixtures of primaryand secondary hydroxyl groups. It is preferred to use .alkylene' oxideswhich contain from 2 to 5 carbon atoms and, generally speaking, it isadvantageous to condense from about 5 to about 30 mols of alkylene oxideper functional group of the initiator. There are many desirableprocesses for the preparation of polyhydric polyalkylene ethersincluding U.S. Pats. 1,922,459; 3,009,939 and 3,061,625 or by theprocess disclosed by Wurtz in 1859 and in Encyclopedia of ChemicalTechnology, vol. 7, pp. 257-262, published by Interscience Publishers,Inc. (1951).

Specific examples of initiators are water, ethylene glycol, 1,2propylene glycol, hexane-1,6 diol, ammonia, ethanolarnine,tripropanolamine, diethanolpropanolamine, tributanolamine, 2,4 tolylenediamine, 4,4 diphenylmethane diamine, p,p',p" triphenylmethane triamine,ethylene diamine, propylene diamine, propylene triamine, N,N,N',N'tetrakis-(2-hydroxypropyl) ethylene diamine, diethylene triamine and thelike. A proportion of a trifunctional starting component, such astrimethylol propane or glycerol, may also be optionally used. It is ofcourse also possible to use mixtures of linear and/or slightly branchedpolyalkylene glycol ethers of different types.

Any suitable polyhydric polythioether may be used such as, for example,the condensation product of thiodiglycol or the reaction product of apolyhydric alcohol such as is disclosed above for the preparation of thehydroxyl polyesters with any other suitable thioetherglycol. Othersuitable polyhydric polythioethers are disclosed in U.S. Pats. 2,862,972and 2,900,368.

The hydroxyl polyester may also be a polyester amide such as isobtained, for example, by including some amine or amino alcohol in thereactants for the preparation of the polyesters. Thus, polyester amidesmay be obtained by condensing an amino alcohol such as ethanolamine withthe polycarboxylic acids set forth above or they may be made using thesame components that make up the hydroxyl polyester with only a portionof the components being a diamine such as ethylene diamine and the like.

Any suitable polyacetal may be used such as, for example, the reactionproduct of formaldehyde or other suitable aldehyde with a polyhydricalcohol such as those disclosed above for use in the preparation of thehydroxyl polyesters.

Any suitable organic dissocyanate may be used in the process of thepresent invention including aromatic, aliphatic and heterocyclicdiisocyanates. In other words, two isocyanate radicals may be bonded toany suitable divalent organic radical to produce the organicdiisocyanates which are useful in accordance with the present inventionincluding acyclic, alicyclic, aromatic and heterof:yclic radicals.Suitable organic polyisocyanates are there ore ethylene diisocyanate,

ethylidene diisocyanate,

propylene-1,2-diisocyanate,

cyclohexylene-1,2-diisocyanate,

m-phenylene diisocyanate,

2,4-tolylene diisocyanate,

2,6-tolylene diisocyanate,

3,3'-dimethyl-4,4-biphenylene diisocyanate,

3,3-dimethoxy-4,4'-biphenylene diisocyanate,

3,3'-diphenyl-4,4'-biphenylene diisocyanate,

4,4-biphenylene diisocyanate,

3,3'-dichloro-4,4-biphenylene diisocyanate,

1,5-naphthalene diisocyanate, furfurylidene diisocyanate and the like.

Examples of preferred dissocyanates include aliphatic diisocyanates,having the general formula OCN (CH -NCO wherein n represents a numberfrom 2 to 8; cycloaliphatic diisocyanates, such ashexahydrotolylene-2,4- and 2,6-diisocyanate and mixtures of theseisomers, or dicyclohexyl methane diisocyanate, araliphatic diisocyanatessuch as 1,3-xylylene diisocyanate, and aromatic diisocyanates such astolylene-2,4- or 2,6-diisocyanate and mixtures of these isomers such asa mixture of 80% 2,4-tolylene diisocyanate and 20% 2,6-tolylenediisocyanate, phenylene- 1,4-diisocyanate, diphenylmethane-4,4'diisocyanate, diphenyl ether 4,4 diisocyanate, naphthylene1,5-diisocyanate and the like. Isophorone diisocyanate and esterdiisocyanates of carboxylic acids of the kind described, for example, inBritish patent specification No. 965,474, may also be used asdiisocyanates in accordance with the invention. Proportions oftriisocyanates such as, p,p,p"-triphenyl methane triisocyanate may beused.

A preferred isocyanate is 2,4 tolylene diisocyanate, however, mixturesof diisocyanates may also be used although it is desirable that at leastabout 50 percent of all of the diisocyanates present have isocyanategroups of different reactivities. Isomeric mixtures of 2,4- and 2,6-tolylene diisocyanate are particularly preferred.

Some preferred compounds which contain at least two hydroxyl groupsreactive with isocyanate groups and having a molecular weight of fromabout 50 to about 500 are slightly branched diols, such as, for example,neopentyl glycol, 1,2 propylene glycol, 1,3 butylene glycol and thelike. Diols which contain hetero atoms, such as, for example, diethyleneglycol, triethylene glycol, dipropylene glycol, tripropylene etherglycol-(1,2), thiodiglycol and the like are also suitable. In addition,it is often desirable to add up to about 25 percent by weight ofhydroxyl compounds which contain at least three hydroxyl groups, suchas, for example, trimethylol propane, to the low molecular weight diols.The compounds containing at least two hydroxyl groups and having amolecular weight of from about 50 to about 500 are preferably used inthe form of isocyanate containing reaction products which are obtainedby carrying out the reaction with an excess of diisocyanate.

"Generally, the quantities in which the reactants are used are selectedin such a way that the molar ratio of diisocyanate to chain extenderplus the compound containing reactive hydroxyl groups, which is governedby the particular processing method used, is generally from 1.0 to 1.5and preferably from 1.05 to 1.25.

It is most desirable that the proportion of hydroxyl content todiisocyanate be such that the amount of free diisocyanate contained inthe resulting prepolymer is less than 10 percent by weight, and mostpreferably, each mol of hydroxyl should be reacted with not more thanabout 1.1 mol of diisocyanate.

The molar ratio of NH groups in the chain-extender to reactive OH groupsmay vary within wide limits, although it is preferably from 0.4 to 1.5,producing soft to hard types of polyurethanes, however, the proportionof N groups in the prepolymer to the amino groups of the chainlengthening agent should be between about 0.8 and about 2.5, preferablybetween about 1.0 and about 1.3.

The process according to this invention may be carried out in manysuitable and different ways. For example, the compound containing atleast two hydroxyl groups may be reacted with an excess of diisocyanateand, after the diamine chain-extender of the invention has been added,the resulting melt is poured into molds. After heating for severalhours, a high grade elastic polyurethane plastic is obtained.

The amine chain-extenders are preferably added to the prepolymers inliquid form at temperatures of from about 50 C. to about 140 C.,preferably from about 80 C.

12 to about C., and after thorough mixing, the melt is poured intopreheated molds. The molded products are removed after about 10 minutesand after about 10 hours storage at about 100 C. they attain their finalmechanical properties.

In another embodiment, the fairly high molecular weight compoundcontaining at least two hydroxyl groups, in admixture with the diaminechain-extender of the invention, is reacted with an excess ofdiisocyanate, and the reaction product is molded under heat and pressureafter it has been granulated. Depending upon the quantities in which thereactants are used, it is possible in this way to obtain polyurethaneplastics with different degrees of hardness and elasticity. In this way,it is possible to obtain plastics which can be processed likethermoplasts. In yet another embodiment, the relatively high molecularweight compound containing at least two hydroxyl groups, in admixturewith the diamine chain-extender of the invention, is reacted with a lessthan equivalent amount of diisocyanate, resulting in the formation of amillable sheet which may be converted in a subsequent stage, forexample, by cross-linking with more diisocyanate, into an elastomericpolyurethane plastic.

In a preferred process according to the invention the compounds ofmolecular weight of from about 800 to about 5,000 which contain at leasttwo hydroxyl groups and the compounds of molecular weight of from about50 to about 500 which have at least two hydroxyl groups are reacted withthe diisocyanates in such a manner that the free diisocyanate content inthe reaction mixture is less than about 10% by weight before thereaction with the aromatic diamines.

According to another preferred procedure, the isocyanate component whichis used consists of reaction prodnets of the diisocyanates with thecompounds of molecular weight of from about 50 to about 500 which haveat least two hydroxyl groups.

According to another preferred method of procedure, the isocyanatecomponent used consists of reaction products of the diisocyanates withneopentyl glycol, propylene glycol-(1,2), butylene glycol-(1,3),diethylene glycol, triethylene glycol, dipropylene glycol, tripropyleneglycol or thiodiglycol to which a proportion of compounds having atleast three hydroxyl groups may have been added.

It is also particularly advantageous to react the higher molecularweight and low molecular weight hydroxyl compounds separately from eachother with a less than equivalent amount of diisocyanates at from about30 C. to about (3., preferably from about 40 C. to about 100 C., andthereafter to mix the two adducts which have an NCO content of fromabout 2% to about 8% and from about 10% to about 25%, respectively,prepolymers which have an NOO content of from about 3% to about 20%being obtained, depending on the proportions in which the two adductshave been mixed.

The elastomeric polyurethanes obtained according to the invention areparticularly valuable when the commercially available isomer mixture of80% by weight of 2,4- and 20% by weight of 2,6-tolylene diisocyanate isused as the diisocyanate.

Although it was known that aromatic diamines containing a chlorine atom,for example, in the o-position to the amino group, may be used aschainextenders in the production of polyurethane elastomers, it wasextremely surprising that the compounds according to the inventionshould be excellent chain-extenders for the production of elasticpolyurethanes. Since aminoesters normally undergo aminolysis at elevatedtemperature, the diamine compounds of the invention, which are besthandled at temperatures above their melting point, had not been expectedto be suitable for use as chain-extenders in the production ofpolyurethanes. Nevertheless, it has been found that, in comparison withelastomeric polyurethane obtained, for example, with3,3-dichloro-4,4-diaminodiphenyl methane as chain extender, polyurethaneelasto- 13 mers prepared with the compounds according to the inventionare distinguished by their greater tensile strength and higherelasticity.

Some of the advantages of the method in which isocyanate-containingprepolymers are used as starting material, using compounds of molecularweight 50 to 5,000 which contain at least two hydroxyl groups, over theuse of free diisocyanate are as follows.

(1) Since the prepolymers contain very little if any unreacteddiisocyanates, they are physiologically harmless since, when usingreadily volatile diisocyanates, the vapor pressure of the freediisocyanate is considerably reduced by doubling the size of themolecule with the low molecular diol.

(2) The pot life of the mixture of prepolymers with chain lengtheningagent is greatly increased since, by using diisocyanates with NCO groupsof diiferent reactivities, the reactive NCO groups have alreadyundergone reaction during prepolymer formation. When using prepolymerswhich have a high free diisocyanate content, this pot life is too shortfor casting to produce large molded products of great hardness.

-(3) In spite of their high content in urea and urea groups, the moldedproducts obtained are transparent whereas when substantial quantities offree diisocyanates are used in the prepolymer the elastomers obtainedare cloudy due to the presence of crystallized urea segments.

(4) For a given NCO number in the prepolymer, the process according tothe invention results in a higher Shore hardness (D scale) which ishigher by about 7 units.

Since only a small amount of reactive isocyanate groups are present, theprepolymers are characterized by increased stability in storage.

The products according to the invention may be used for a variety ofpurposes including, for example, the production of moldings of the kindused in machine or vehicle construction, for example, in the manufactureof gear rings, V-belts, gear wheels, bearing shells, seals, diaphragmsand the like. The polyurethanes may be modified with the usualadditives, for example, dyes, pigments or fillers if desired.

The invention is further illustrated but is not intended to be limitedby the following examples in which all parts and percentages are byweight unless otherwise specified.

(EXAMPLE 1 About 1 mol of potassium hydroxide is dissolved in about 800ml. of methanol. About 1 mol of 4-chloro-3,5- dinitrobenzoic acid methylester is added in portions with cooling. The reaction mixture is thenheated under reflux until the reaction is at an end, as shown by achange in the originally violet color to yellow.4-methoxy-3,5-dinitrobenzoic acid methyl ester crystallizes out oncooling. Yield: 205 g. MIP. 53 C.-55 C.

About 100 parts of this compound are hydrogenated with 20 parts of Raneynickel B in about 400 ml. of dioxan. About 70 parts of4-methoxy-3,S-diaminobenzoic acid methyl ester melting at 157 C.-l58 C.are obtained following recrystallization from methanol.

Calculated (percent): C, 55.1; H, 6.2; N, 14.3. Found (percent): C,55.2; H, 5.4; N, 14.2.

EXAMPLE 2 o o-o-on,

HgN NH:

About 200 parts of 4-chloro-3,S-dinitrobenzoic acid methyl ester, whichcan be obtained by nitrating chlorobenzoic acid at about C.-140 C. andesterifying the resulting 4-chloro-3,S-dinitrobenzoic acid withmethanol, are hydrogenated at room temperature with 40 parts of Raneynickel and 30 parts of sodium bicarbonate in about 500 ml. of dioxan.About 140 parts of 4-chloro- 3,5-diaminobenzoic acid methyl estermelting at 128 C.- 129 C. are obtained after recrystallization frommethanol/ water.

Calculated (percent): C, 47.9; H, 4.5; N, 14.0; C1, 17.6. Found(percent): C, 47.8; H, 4.7; N, 13.9; CI, 17.7.

HrN

About 1 mol of 4-chloro-3-nitrobenzoyl chloride dissolved in about 200ml. of acetone are added dropwise in a nitrogen atmosphere at about 20C. to about 40 C. to a solution of about 1 mol of 3-chloro-4-nitrophenolin 1 liter of normal caustic soda solution. About 310 parts of4-chloro-3-nitrobenzoic acid-(3'-chloro-4'-nitro)- phenyl ester meltingat 157 C.-l58 C. are obtained after recrystallization from toluene.

Calculated (percent): C, 43.7; H, 1.7; N, 7.9; Cl, 19.9. Found(percent): C, 43.7; H, 2.0; N, 7.8; Cl, 20.0.

About 200 parts of this compound are hydrogenated at about 20 C. to 40'C. with 40 parts of Raney nickel B and about 30 parts of sodiumbicarbonate in about 750 ml. of dioxan. Recrystallization from dimethylformamide/water gives parts of 4-chloro-3-aminobenzoicacid-(3-chloro-4-amino)-phenyl ester melting at 145 C.-l46 C.

Calculated (percent): (3, 52.6; H, 3.3; N, 9.4; Cl, 23.9. Found(percent): C, 52.5; H, 3.7; N, 9.5; Cl, 23.5.

[EXAMPLE 4 HzN-Q-C 0-O-QNH:

Following the procedure described in Example 3, about 260 parts of4-nitrobenzoic acid-(3'-chloro-4-amino)- phenyl ester melting at 157C.-l58 C. are obtained with about 1 mol of 4-nitrobenzoyl chloride.

Calculated (percent): C, 50. 6; H, 2.3; N, 9.1; Cl, 11.5. Found(percent): C, 50.4; H, 2.5; N, 9.0; CI, 11.3.

About 120 parts of 4-aminobenzoic acid-(3'-chloro-4- amino)-phenyl esterare obtained by hydrogenating this compound in accordance with theprocedure described in Example 3. M.P. 138 C.140 C.

Calculated (percent): C, 59.5; H, 4.2; N, 10.7; C1, 13.5. Found(percent): C, 59.8; H, 4.3; N, 10.8; C1, 13.4.

EXAMPLE 5 l HzN 1 1E:

Following the procedure described in Example 3, about 285 parts of4-chloro-3-nitrobenzoic acid-(4'-chloro-3- n1tro)-phenyl ester meltingat 128 C. are obtained with about 1 mol of 4-chloro-3-nitrophenol.

Calculated (percent): C, 43.7; H, 1.7; N, 7.8; Cl, 19.9. Found(percent): C, 43.5; H, 2.0; N, 7.8; CI, 20.0.

About 140 parts of 4-chloro-3-aminobenzoic acid-(4'-chloro-3'-amino)-phenyl ester are obtained by hydrogenation inaccordance with the procedure described in Example 3. M.P. 147 C.l48 C.

Calculated (percent): C, 52.6; H, 3.3; N, 9.4; CI, 23.9. Found(percent): C, 52.8; H, 3.7; N, 9.5; CI, 23.5.

1 EXAMPLE 6 About 2 mols of 4-chloro-3-nitrobenzoic acid are heatedunder nitrogen for about 8 hours at about 100 C. with about 1 mol ofethylene glycol and about 1 ml. of about 36% hydrochloric acid, and thenfor about 5 hours at about 160 C. The dinitro compound formed (about 350parts) melts at 160 C. after recrystallization from benzene.

Calculated (percent): C, 44.8; H, 2.4; N, 6.7, Cl, 16.6. Found(percent): C, 45.1; H, 2.6; N, 6.3; Cl, 16.7.

Following hydrogenation in accordance with the procedure described inExample 2, ethylene glycol-bis-(4- chloro-3-amino)-benzoic acid ester isobtained, melting at 171 C. after recrystallization.

Calculated (percent): C, 52.1; H, 3.8; N, 7.6; Cl, 19.2. Found(percent): C, 52.4; H, 3.9; N, 7.5; Cl, 18.9.

EXAMPLE 7 o HzN-Q-O-Hl-O-Q-Nlla About 2 mols of 3-chloro-4-nitrophenolare dissolved under nitrogen in about 100 ml. of twice normal sodiumhydroxide solution. A vigorous stream of phosgene is introduced at about20 C. to 40 C. The 3,3'-dichloro- 4,4-dinitrodiphenyl carbonate whichprecipitates is suction filtered and recrystallized from toluene, M.P.151 C.

Calculated (percent): C, 42.0; H, 1.6; N, 7.5; CI, 19.1. Found(percent): C, 42.1; H, 1.7; N, 7.4; Cl, 19.3.

3,3'-dich1oro-4,4'-diaminodiphenyl carbonate is obtained byhydrogenation in accordance with the procedure described in Example 3.M.P. 166168 C.

Calculated (percent): C, 49.9; H, 3.1; N, 8.9; Cl, 22.6. Found(percent): C, 50.2; H, 3.4; N, 9.1; CI, 22.2.

:EXAMPLE 8 4,4'-dichloro-3,3'-dinitrodiphenyl carbonate melting at 183C.-185 C. is prepared in accordance with the procedure described inExample 7.

Calculated (percent): C, 42.0; H, 1.6; N, 7.5; Cl, 19.1. Found(percent): C, 41.9; H, 1.8; N, 7.3; CI, 19.1.

4,4'-dichloro-3,3'-diamino diphenyl carbonate is obtained byhydrogenation in accordance with Example 3. M.P. 192 C.-193 C.

Calculated (percent): C, 49.9; H, 3.1; N, 8.9; Cl, 22.6. Found(percent): C, 50.1; H, 3.1; N, 9.2; Cl, 22.8.

EXAMPLE 9 About 2 mols of 3-chloro-4-nitrophenol are dissolved in about1000 ml. of twice normal sodium hydroxide solution, about 1 mol ofsuccinic acid dichloride being added dropwise to the resulting solutionunder nitrogen at a temperature of from about 20 C. to 40 C.

The product which precipitates is filtered off under suction. Succinicacid di-(3-chloro-4-nitro)-phenyl ester melting at 96-97 C. is obtainedafter drying and recrystallization from benzene/cyclohexane.

Calculated (percent): C, 44.8; H, 2.4; N, 6.5; CI, 16.6. Found(percent): C, 45.0; H, 2.6; N, 6.3; Ci, 16.3.

Succinic acid di-(3-chloro-4-amino)-phenyl ester melting at 196 C.-l98C. (from dioxan) is obtained by hydrogenation in accordance with theprocedure described in Example 3.

Calculated (percent): C, 52.1; H, 3.8; N, 7.6; Cl, 19.2. Found(percent): C, 52.1; H, 4.0; N, 7.7; Cl. 18.8.

EXAMPLE 10 About 200 parts of a polyester of adipic acid and andethylene glycol (OH number 56) are dehydrated in vacuo for about 15minutes at about 130 C. About 40 parts of a mixture of of 2,4- and 20%of 2,6- tolylene diisocyanate are then added. After about 30 minutes,about 29.7 parts of the compound of Example 3 are added in the form of amelt. After an interval of about 20 seconds, the homogeneous melt ispoured into preheated molds and heated for about another 24 hours atabout C. The polyurethane elastomer formed has the following mechanicalproperties:

Tensile strength (DIN 53504) kg/cm?" 321 Breaking elongation (DIN 53504)percent 625 Permanent elongation (1 minute after tearing) percent 9Intrinsic strength kp 48 Shore hardness A (DIN 53505) 88 Elasticity (DIN53512) percent 30 COMPARISON EXAMPLE The procedure is as described inExample 10 except that about 27 parts of3,3-dichloro-4,4-diaminodiphenyl methane is used as the chain-extender.The polyurethane elastomer formed shows the following mechanicalproperties:

Tensile strength (DIN 53503) kg./cm. 234 Breaking elongation (DIN 53504)percent 440 Permanent elongation (1 minute after tearing) percent 11Intrinsic strength kp 37 Shore hardness A (DIN 53505) 84 Elasticity (DIN53512) percent 31 EXAMPLE 11 The procedure is as described in Example 10except that about 26.2 parts of the diamine according to Example 4, isused as the chain-extender. A polyurethane elastomer with the followingmechanical properties is obtained:

Tensile strength (DIN 53504) "kg/cm? 333 Breaking elongation (DIN 53504)percent 645 Permanent elongation (1 minute after tearing) percent 7Intrinsic strength kp 38 Shore hardness A (DIN 53505) 87 Elasticity (DIN53512) percent 30 EXAMPLE 12 The procedure is as described in Example10, except that about 36.9 parts of the diamine according to Example 6are used. The resulting polyurethane shows the following mechanicalproperties:

Tensile strength (DIN 53504) kg./cm. 322 Breaking elongation (DIN 53504)percent 683 Permanent elongation (1 minute after tearing) percent 6Intrinsic strength kp 70 Shore hardness A (DIN 53505) 88 Elasticity (DIN53512) percent 27 EXAMPLE 13 The procedure is as described in Example 10except that about 31.3 parts of the diamine according to Example 7 fusedwith about 20 parts of a polyester of adipic 17 acid and ethylene glycol(OI-I number 56), are used. The resulting polyurethane shows thefollowing mechanical properties:

Tensile strength (DIN 53504) kg./cm. 254 Breaking elongation (DIN 53504)percent 715 Permanent elongation (1 minute after tearing) percent 15Intrinsic strength kp 40 Shore harness A (DIN 53505) 80 Elasticity (DIN53512) percent 28 EXAMPLE 14 The procedure is as described in Example10, except that about 36.9 parts of the diamine according to Example 9are used. A polyurethane with the following mechanical properties isobtained:

Tensile strength (DIN 53504) kg./cm. 204 Breaking elongation (DIN 53504)percent 655 Permanent elongation (1 minute after tearing) percent 18Intrinsic strength kp 36 Shore hardness A (DIN 53505 85 Elasticity (DIN53512) percent 29 EXAMPLE 15 The procedure is as described in Example10, except that about 20.1 parts of the diamine according to Example 2are used. An elastomeric polyurethane with the following mechanicalproperties is obtained:

ethylene glycol (OH number 566), about 33.2 parts of a mixture of 80% of2,4- and 20% of 2,6-tolylene diisocyanate and about 13.7 parts of4-methoxy-3,5-diaminobenzoic acid methyl ester according to Example 1,are reacted in accordance with the procedure described in 'Example 10 togive a polyurethane with the following mechanical properties:

Tensile strength (DIN 53504) kg./cm. 308 Breaking elongation (DIN 53504)percent 680 Permanent elongation (1 minute after tearing) percent 6Intrinsic strength kp 66 Shore hardness A (DIN 53505) 85 Elasticity (DIN53512) percent 40 EXAMPLE 17 About 200 parts of a polyester of adipicacid and ethylene glycol (OH number 56), about 31.2 parts of a mixtureof 80% of 2,4- and 20% of 2,6-to1ylene diisocyanate and about 12 partsof 4-chloro-3,5-diarninobenzoic acid methyl ester are reacted inaccordance with Example 10 to form a polyurethane with the followingmechanical porperties:

Tensile strength (DIN 53504) kg./cm. 324 Breaking elongtion (DIN 53504)percent 657 Permanent elongation (1 minute after tearing) percent 7 7Intrinsic strength kp. 52 Shore hardness A (DIN 53504) 83 Elasticity(DIN 53512) percent 40 EXAMPLE 18 About 200 parts of apolytetramethylene glycol (OH number 53.5), about 38.3 parts of amixture of 80% of 2,4- and 2 of 2,6-to1ylene diisocyanate and about 28.4

parts of the diamine according to Example 3 are reacted in accordancewith Example 10 to form a polyurethane showing the following mechanicalproperties:

Tensile strength (DIN 53504) kg./cm. 170 Breaking elongation (DIN 53504)percent 442 Permanent elongation (1 minute after tearing) percent 6Intrinsic strength -kp 22 Shore hardness A (DIN 53505 82 Elasticity (DIN53512) upercent". 51

EXAMPLE 19 Following the procedure described in Example 18, apolyurethane with the following mechanical properties is obtained withabout 26.3 parts of the diamine according to Example 4:

Tensile strength (DIN 53504) kg./cm. 238 Breaking elongation (DIN 53504).percent 535 Permanent elongation (1 minute after tearing) percent 10Intrinsic strength kp 33 Shore hardness A (DIN 3505) 92 Elasticity (DIN53512) ..percent 52 EXAMPLE 20 About 200 parts of a polytetramethyleneglycol ether (OH number 56), about 32. 6 parts of a mixture of of 2,4-and 20% of 2,6-tolylene diisocyanate and about 16.3 parts of the diamineaccording to Example 2 are reacted in accordance with the proceduredescribed in Example 18. The resulting polyurethane has the followingmechanical properties:

Tensile strength (DIN 53504) "kg/cm 110 Breaking elongation (DIN 53504)percent 858 Permanent elongation (1 minute after tearing) percent 10Intrinsic strength kp 37 Shore hardness A (DIN 53505) Elasticity tpercent- 50 EXAMPLE 21 Following the procedure described in Example 18,a polyurethane showing the following mechanical properties is obtainedwith about 31.3 parts of the diamine according to Example 7:

Tensile strength (DIN 53504) kg./cm. 168 Breaking elongation (DIN 53504)percent 560 Permanent elongation (1 minute after tearing) percent 10Intrinsic strength kp 37 Shore hardness A (DIN 53505) 85 Elasticity (DIN53512) percent 50 EXAMPLE 22 About 200 parts of a polytetramethyleneglycol ether (OI-I number 53.5), about 29.8 parts of a mixture of 80%2,4- and 20% 2,6-tolylene diisocyanate and about 11.8 parts of thediamine according to Example 1 are reacted in accordance with theprocedure described in Example 10. The resulting polyurethane has thefollowing mechanical properties:

Tensile strength (DIN 53504) kg./cm. 108 Breaking elongation (DIN 53504)percent 495 Permanent elongation (1 minute after tearing) percent 7Intrinsic strength kp 21 Shore hardness A (DIN 53505) 78 Elasticity (DIN53512) percent 56 It is to be understood that any of the components andconditions mentioned as suitable herein can be substituted for itscounterpart in the foregoing examples and that although the inventionhas been described in considerable detail in the foregoing, such detailis solely for the 19 purpose of illustration. Variations can be made inthe invention by those skilled in the art without departing from thespirit and scope of the invention.

EXAMPLE 23 200 g. of 4-chloro-3,5-dinitrobenzoic acid ethyl ester, whichcan be obtained by nitrating p-chlorobenzoic acid at 80 to 100 C. andesterifying the resulting 4-chloro- 3,5-dinitrobenzoic acid with ethanolare added dropwise in the form of a solution in 1 l. of toluylene to theboiling mixture of 500 g. of water, 500 g. of iron powder, 5 g. ofglacial acetic acid and 500 ml. of toluene. After neutralisation withsodium bicarbonate there are obtained 136.8. (87% of the theoretical)(melting point 135 C.) of the analytically pure4-chloro-3,S-diaminobenzoic acid ethylester (NH-number 524) afterseparating of the iron sludge by cooling the toluene solution.

In analogous manner there are obtained the following compounds:

Following the procedure described in Example poly- 0.1 mol of diaminesaccording to Examples 2329.

20 of hydrogen chloride ceases. The excess thionylchloride is distilledoil and the residue esterified with 220 g. (2.2. mols) of hexanol-( 1).When the evolution of hydrogen chloride has terminated the reactionproduct is recrystallized from 900 g. of methanol.

Yield: 603 g. (91.5%). Melting point: 5152 C.

In a vessel of which is equipped with stirrer equipment 600 g. (1.81mol) of 4-chloro-3,5-dinitrobenzoic acid hexylester, dissolved in 1 l.of toluene is added dropwise to a boiling mixture of 1200 g. of Water,1200 g. of iron powder, 12 of glacial acetic acid and 1 l. of toluene.

The reduction is completed after 4 hours. For neutralisation thereaction mixture is treated with 17 g. of sodium hydrogen carbonate andthe water separated off in a separating funnel. After filtration anddistilling of the toluene there are obtained 460 g. of a crystallinediamine. Pure 4-chloro-3,S-diaminobenzoic acid hexylester is obtainedafter recrystallisation from a mixture of 400 g. of benzene and 80 g. ofcyclohexane.

Yield: 388 g. (83%). Melting point: 81-83 C. NH; number: 430.

-In analogous manner the following diamines are ob tained:

--CHr-CH:0C4H| 58 395 (theoretical 391).

Tensile Breaking Permanent Shorestrength, elongation, elongationIntrinsic hardness Elasticity, kg./e1:n. percent after tearstrength,.A/D (DIN percent Example Amine, g. (DIN 53504) (DIN 53504) ing, percentkp. 53505) 53512) 30 215 g. acc., Example 23 319 627 16 92/38 36 31-22.8 g. 5200., Example 24- 341 602 12. 5 46. 5 93/41 34 32. 22.8 g.200., Example 25 365 607 11 73 93/42 35 33- 24.3 g. acc.-, Example 26.322 613 17. 5 61 93/38 34 34.--- 24.3 g. acc., Example 27 355 637 16 6390/40 33 35 24.3 g. acc., Example 28 342 602 14 69 93/39 35 36 24.45 g.300., Example 29 355 585 9. 5 51 92/40 34 EXAMPLE 37 Production of thepolyurethane elastomers C O C H 200 g. of a polyester of adipic acid andethylene glycol 2 (0H number 56) are dehydrated at 130 C. for 10 minutesin a water jet vacuum.

40 g. of a mixture consisting of 80% of 2,4-toluene-d1- H N isocyanateand 20% of 2,6-toluene-diisocyanate are added 2 and the mixture isstirred for another 30 minutes. The melt Cl is then cooled to 110 C. anddegasiiied for 1 minute by 70 the application of a vacuum.

493 g. (2 mols) of 4-chloro-3,S-dinitrobenzoic acid are suspended in 500ml. of benzene.

357 g. of thionylchloride are slowly added dropwise at 70 to C. and themixture is refluxed upon the addi- 0.1 mol of the amines according tothe invention are added in liquid form. After an interval of 20 secondsthe melt is poured into a preheated mould and the rapidly hardeningmoulding is heated at C. for another 24 tion of 10 g. ofdimethylformamide until the evolution 75 hours.

21 22 Mechanical properties:

Permanent Tensile elongation Shorestrength, Breaking after Intrinsichardness Elasticity kgJcm. elongation, tearing,- strength, A/D percentExample Diamine, g. (DIN 53504) percent percent; kp. (DIN 53505) (DIN53512) 45 26.05 g. acc., Example 37 841 620 18 44 93/35 36 46 27.05 g.acc., Example 38 336 573 8 4 88/ 35 47 29.85 g. 2100., Example 39 356620 18 43 91/34 34 48 43.85 g. acc., Example 40 277 600 35 32 92/39 3749 28.65 g. MP 338 665 19 43 91/40 37 EXAMPLE 50 Tensile strength (DIN53504) "kg. wt./cm. 640 About 200 parts of a polyester of adipic acidand fi g at 3 332 535504) "Percent" 2 ethylene glycol (OH number 56),about 63.3 parts of 5350 4 2,4-tolylene diisocyanate and about 57.5parts of 4chloroastmty (D1 3512) "percent" 4 3,5-diaminobenzoic acidisobutylester according to Example 27, are reacted in accordance withthe procedure described in Example 10 to give a polyurethane with thefollowing mechanical properties.

Tensile strength (DIN 53504) kg./cm. 321 Breaking elongation (DIN 53504)percent 445 Permanent elongation '(1 minute after tearing) "percent" 35Intrinsic strength kp 43 Shore hardness D (DIN 53505) 55 Elasticity (DIN53512) percent 40 EXAMPLE 51 About 1200 parts of a polyester of adipicacid and ethylene glycol (OH number 59) are melted at about 130 C. undernitrogen and dehydratedat 130 C.

About 224 parts of 2,4-tolylcne diisocyanate are added at about 60 C.with stirring. After about 24 hours storage at about 60 C., a prepolymerwhich has an NCO content of about 3.95% (based on parts of NCO per partof prepolymer) and a viscosity of about 900 cp. at about 90 C. (measuredin a Hoppler viscosimeter) is obtained.

EXAMPLE 52 About 106 parts (1 mol) of diethylene glycol are addeddropwise to about 380 parts of 2,4-tolylene diisocyanate under nitrogenat from about 40 C. to about 50 C. The reaction is terminated afterabout 2 hours. The prepolymer obtained has an NCO content of about20.8%.

EXAMPLE 53 content of prepolymer the adduct, according to The mechanicalproperties shown in Table 3 are obtained in analogous manner by mixingthe prepolymers of Examples 51 and 52 according to the recipes shown inTable 2.

TABLE 2 Parts 0! Parts of prepolymer of isobutyl;- Exampl chime-3,5- Vdiamino- 2 1 benzoate Example TABLE 3 Tensile Elonga- Shore strength 1tion at hardness Elasticity (kg. wt break 1 D (DIN (DIN 53512) cm?)(percent) 53505) (percent) Example:

1 DIN 53504.

In Example 61, the pot life of the mixture of prepolymer with chainlengthening agent is about 150 seconds, whereas when the followingrecipe is used, the pot life is only about 30 seconds. The times forremoval from the mold are in most cases from about 400 to about 500seconds.

Comparison example A mixture of about 191 parts of the prepolymer ofExample 51 and about 9 parts of 2,4-tolylene diisocyanate is degasifiedat about 100 C., and after mixing with about 30 parts of isobutyl4-chloro-3,5-diamino-benzoate, the mixture is rapidly poured into molds.

Part of N00 content viscosity of the mixture Percent Op. 90 C.

Example Mol of dlol percent Example 1 54 Neopentylglycol. 20. 3 2,900 5.9 850 55- Triethylene glycol. .5 18. 8 2, 940 6 800 56- 1,2-propyleneglycol 20. 9 2,820 6. 0 820 57- Dipropylene glycoll9. 3 2, 850 5. 9 78058 Thiodiglyool 19. 8 480 12. 5 600 The product can be removed from themold after about EXAMPLE 59 6 minutes. The molded product is hardenedfor about 24 hours at about C. and has the following mechanicalproperties.

Example Tensile strength (DIN 53504) (k .lcmfl) 1 850 l 325 Elongationat break (DIN 53504 (percent) 1 600 l 610 Permanent elongation 1 mm.after tearing (percent) 1 25 1 29 1 Determined on the ring.

23 EXAMPLE 64 tion of about 30.5 parts of isobutyl4-chloro3,5-diaminobenzoate. The melt is poured into molds and hardenedat about 100 C. After about 24 hours, the following mechanicalproperties are obtained.

Tensile strength (DIN 53504) (kg. "wt/cm?) 355 Elongation at break (DIN53504) (percent) 352 Shore hardness D (DIN 53505) 57 Elasticity (DIN53512) (percent) 39 1400 cp. at about 90 C. Although the invention hasbeen described in consider- By using the prepolymers of Examples 51 to58 and 64 able detail in the foregoing, such detail is solely for theeither alone or in admixture, hard transparent elastomers purpose ofillustration. Variations can be made in the inhaving the mechanical r0erties shown in Table 4 are vention by those skilled in the art withoutdeparting from p p n n u u I obtained in a manner analogous to Example59 using the the spirit and scope of the invention except as 1s setrecipes shown in Table 4. forth in the claims.

TABLE 4 Parts of Parts of preisobutyl 4- Iensile Elongapolymerehloro-3,5- strongth tion at Elasticity Shore hard- Parts of prepolymerof 01 Example dlarnino- (kg. wt./ break 1 (DIN 53512) ness D example 64benzoate emfl) (percent) (percent) (DIN 53505) Example:

65 175, Example 54 27. 6 747 540 39 56 66.. 177, Example 55.-. 27. 1 681527 40 5e 67 174, Example 56. 27. 4 541 477 40 57 176.8, Example 5 27.8668 551 40 55 69.. 140 46, Example 58-- 29.3 676 559 42 54 7o 12051.5,Example53 5 30.1 731 493 43 59 71 120 40.8, Example 53.... 15.530.1 763 481 41 59 1 DIN 53504.

EXAMPLE 73 What is claimed is:

About 114 parts of a polyester of adipic acid and polyurehhane elastomerprepared a process hexanediol (OH number 133) are dehydrated undercompnsmg reacting an Orgamc compound I at least vacuum at about 130 C.about 36 parts of 2,4-tolylene two hydroxyl groups and a molqculafwelght of from diisocyanate are added at about After about 4 about 800to about 5000, an organic diisocyanate and an hours at about 80 0.,about 30.5 parts of the prepolymer atomfltlc l p cham'extendmg agent iaromaiuc of Example 52 are added. The mixture is degasified at dlammeconfmmmg an ester group pf the ammo about 100 C. by applying a vacuum.About 30.8 parts of groups are m 5 meta" para'posltlon to the Esterisobutyl 4-chloro-3,5-diaminobenzoate are stirred in as a grou? acontammg a Substltuent Selected the group melt at about 100 C. and themelt is poured into preconslstmg of haloger. or an alkoxy havmg from 1heated molds after agout 30 seconds After about 24 40 to carbon atoms Inthe ortho-position to at least one 0 rs t t bo th follow'n mechanicalammo group g g i g z z ga 100 e 1 g 2. The elastomer of claim 1 whereinthe reaction is conducted in the presence of an organic compound hav-Tenslle Strength 53504) g- 622 ing at least two hydroxyl groups and amolecular weight Elongation at break (DIN 53504) (percent) 319 of f omabout to about 5 Shf11aTdne$S D 53505) 64 3. The elastomer of claim 2wherein the compounds E1a5t1c1tY(DIN 53512) (P 0 31 having at least twohydroxyl groups and a molecular EXAMPLE 74 About 120 parts of apolytetramethylene ether glycol (OH number 116) are dehydrated in avacuum at about 130 C. About 35.2 parts of 2,4-tolylene diisocyanate areadded at about 80 C. After about 2 hours, about 25.3 parts of theprepolymer of Example 52 are added and degasified at about 100 C. byapplication of a vacuum. After the addition of about 30 parts ofisobutyl 4-chloro- 3,5-diaminobenzoate, the melt is poured into molds.The product can be removed from the molds after about 10 minutes atabout 100 C. After about 24 hours storage at about 100 C., the followingmechanical properties are obtained.

Tensile strength (DIN 53504) (kg. wt./cm. 518 Elongation at break (DIN53504) (percent) 414 Shore hardness D (DIN 53505) 54 Elasticity (DIN53512) (percent) 42 EXAMPLE 75 About 117 parts of a polypropylene etherglycol-(1,3) (OH number 110) are dehydrated at about 130 C. byapplication of a vacuum. About 33 parts of 2,4-tolylene diisocyanate areadded at about 80 C. about 29.5 parts of the prepolymer of Example 52are added after about 24 hours at about 80 C. Degasification is thencarried out at about 100 C. by application of a vacuum and the melt ishomogenized for about 30 seconds after the addiweight of from about 800'to about 5000 and the compounds having at least two hydroxyl groups anda molecular weight of from about 50 to about 500 are reacted with theorganic diisocyanate such that the free diisocyanate content in thereaction mixture is less than about 10 percent by weight, prior toreaction with the aromatic diamine chain-extender.

4. The elastomer of claim 1 wherein the diisocyanate component used is areaction product of an organic diisocyanate and a compound having atleast two hydroxyl groups and a molecular weight of from about 50 toabout 500.

5. The elastomer of claim 4 wherein the diisocyanate component is areaction product of an organic diisocyanate with a compound having atleast two hydroxyl groups and a molecular weight of from about 50 toabout 500 said compound selected from the group consisting of neopentylglycol, 1,2-propylene glycol, 1,3-buty1ene glycol, diethylene glycol,triethylene glycol, dipropylene glycol, tripropylene glycol, andthiodiglycol.

6. The elastomer of claim 5 wherein the compounds having at least twohydroxyl groups and a molecular weight of from about 50 to about 500contain up to about 25 percent of weight of a compound which contains atleast three hydroxyl groups.

7. The elastomer of claim 6 wherein the compound which contains at leastthree hydroxyl groups is trimethylol propane.

8. The elastomer of claim 1 wherein the diamine has the general formula(|JO--R HaN --NH,

HzN NH: x Y Y wherein X is selected from the group consisting ofhydrogen or halogen atom and Y is a halogen atom.

10. The elastomer of claim 1 wherein the diamine has the formula whereinA is a divalent alkylene radical having from 2 to 6 carbon atoms whichmay contain oxygen, sulfur or -N('R) (R=C -C -alkyl).

11. The elastomer of claim 1 wherein the diamine has the formula HzN Hawherein each X is a halogen atom and in which at least one substituent Xis in the ortho-position to the amino group.

12. The elastomer of claim 1 wherein the diamine has the formula whereinn is a number of from 0 to 4 and each X is a halogen atom and in whichat least one substituent X is in the ortho-position to the amino group.

13. The elastomer of claim 8 wherein the diamine has the formula whereinR is selected from the group consisting of CH;;, '-C2H5, -CgH-; 01-iS0-C H 14. The elastomer of claim 8 wherein the diamine has theformula 5 HzN NH,

15. The elastomer of claim 9 wherein the diamine has the formula 16. Theelastomer of claim 9 wherein the diamine has the formula 17. Theelastomer of claim 10 wherein the diamine has the formula I HaN 11TH!wherein n is a number of from 2 to 6.

18. The elastomer of claim 11 wherein the diamine has the formula 19.The elastomer of claim 12 wherein the diamine has the formula wherein nis a number of from 0 to 4.

References Cited UNITED STATES PATENTS 3,457,234 7/1969 Gianatasio 260-NH 3,095,399 6/1963 Muller et al. 260-471 R DONALD E. CZAJA, PrimaryExaminer M. I. WELSH, Assistant Examiner US. Cl. X.R. 260-471 R

